Do Isoflavones Reduce Breast Cancer Risk?
By Anthony Almada, MS
Abundant in soy and red clover, isoflavones are often consumed to reduce breast cancer risk, build bones and to help treat menopausal symptoms. Isoflavones, such as genistein, are considered phytoestrogens because they are a plant-derived chemical that exhibits mild estrogenlike effects.
Despite the growing popularity of isoflavones, no evidence supports their long-term safety, efficacy or lack of adverse side effects in treating women with, or at risk for, breast cancer. Animal studies have been inconclusive. They've shown both a preventive effect against chemical-induced breast cancer and a promoting effect in animals implanted with breast cancer cells. Researchers conducting the latter studies employed the same research model used to validate the breast cancer drug tamoxifen, formulated to resemble the naturally occurring estrogen in postmenopausal women.
One area of research that needs more exploration is the interaction between tamoxifen and isoflavone-rich products when both are used by breast cancer survivors. In a recent study, researchers found that the drug and the phytoestrogen worked together to provide a positive health benefit.
Nutrition and exercise biochemist Anthony Almada, MS, has collaborated on more than 45 university-based studies, is cofounder of Experimental and Applied Sciences (EAS), and founder and chief scientific officer of IMAGINutrition.